Rockin' music! This is a cool design, I regret it was too hard for me to get far. At first I was having a lot of trouble with the default form being too fast for staying on platforms. Where I finally got stuck was a section of 3 glass walls along a conveyor which seemed to require 1) Jump as the default slime, 2) Transform into the stone crab in midair, 3) Break a glass wall before hitting the ground, 4) Without also accidentally breaking the lowest section of glass (which holds you on each of the three stages of this challenge, otherwise you have to do them all in quick succession); this requires a pressing right and jump, then shifting to Q, the clicking the mouse, which was too much for me to handle with the requisite timing. There was a lot of "rule of 3" in the level design, this can be effective but here it mostly seemed repetitive.
I'd be happy to play a more forgiving version if you continue with it!